Just a simple verilator skeleton project for verilog co-simulation.
$> make
$> ./simulator
k = 0, sw = 0, led = 1
k = 1, sw = 1, led = 0
k = 2, sw = 0, led = 1
k = 3, sw = 1, led = 0
k = 4, sw = 0, led = 1
k = 5, sw = 1, led = 0
k = 6, sw = 0, led = 1
k = 7, sw = 1, led = 0
k = 8, sw = 0, led = 1
k = 9, sw = 1, led = 0
k = 10, sw = 0, led = 1
k = 11, sw = 1, led = 0
k = 12, sw = 0, led = 1
k = 13, sw = 1, led = 0
k = 14, sw = 0, led = 1
k = 15, sw = 1, led = 0
k = 16, sw = 0, led = 1
k = 17, sw = 1, led = 0
k = 18, sw = 0, led = 1
k = 19, sw = 1, led = 0